•Urinary 3-OHBaP is a biomarker for assessing carcinogenic PAH exposure in human.•IL-DLLME was used for trace 3-OHBaP enrichment the first time.•Lowering environmental toxicity and increasing extraction efficiency.•Chemical derivatization using dansyl chloride enhanced HPLC-HRMS/MS response.•Method validation results demonstrated satisfactory analytical performance.3-Hydroxybenzo[a]pyrene (3-OHBaP) is widely used as a biomarker for assessing carcinogenic benzo[a]pyrene exposure risks. However, monitoring urinary 3-OHBaP suffers from an insufficient sensitivity due to the pg/mL level in urine excretion. In this study, a sensitive method for determination trace urinary 3-OHBaP was developed, involving enzymatic hydrolysis of the glucuronide and sulfate conjugates, ionic liquids dispersive liquid–liquid microextraction (IL-DLLME) enrichment, derivatization with dansyl chloride and HPLC-HRMS/MS analysis in the positive ion mode. Using IL-DLLME makes the enrichment of trace 3-OHBaP very simple, time-saving, efficiency and environmentally-friendly. To enhanced HPLC-HRMS/MS response, an MS-friendly dansyl group was introduced to increase the ionization and fragmentation efficiency. The optimal IL-DLLME extraction parameters and derivatization reaction conditions were investigated. Good linearity was obtained over a concentration range of 0.6–50.0 pg/mL with correlation coefficients (r2) of 0.9918. The limit of detection (LOD) and limit of quantification (LOQ) values were 0.2 pg/mL and 0.58 pg/mL, respectively. The recoveries were 92.0 ± 4.2% with the intra-day and inter-day RSD values ranged from 2.2% to 3.8% and from 3.3% to 6.8%, respectively. The proposed IL-DLLME-Dansylation-HPLC-HRMS/MS method was successfully applied to determine urinary 3-OHBaP of non-occupational exposed smokers and nonsmokers.

•We fabricate a novel DVB/Fe3O4 hybrid monolith by in situ polymerization.•MeHg in sample solution is enriched on the monolith.•Electromagnetic induction heating is used for online thermal desorption.•Limit of detection for MeHg is as low as 0.09 ng L−1.A novel method of divinylbenzene polymer (DVB)/Fe3O4 hybrid monolithic column solid phase extraction and on line thermal desorption was developed to analyze methylmercury (MeHg) in water and fish samples. The monolithic column was prepared by in situ polymerization in silica tube and its heating characteristic was studied in detail. Special accent was put on the study of parameters influencing adsorption and desorption of MeHg, such as pH, flow rate of sample solution, temperature of desorption and flow rate of carrier. Under optimum conditions, the detection limit and relative standard deviation of MeHg were 0.09 ng L−1 and 2.6% (10 ng L−1, N=11), respectively. Recoveries of MeHg were never less than 96%. Standard reference material GBW10029 was analyzed for validation of the methodology. This method was successfully applied to the determination of MeHg in water and fish samples.

In this paper we discuss an on-line electrokinetic extraction and electrochemical hydride generation system for inorganic arsenic speciation developed using an H-type integrated cell. The integrated cell, mainly consisting of a working chamber and an auxiliary chamber, was used as both an electrokinetic extraction and an electrochemical hydride generation unit. The As(V) ions in the sample solution was firstly extracted into the working chamber of the H-type integration cell and reduced into As(III). Subsequently, the integrated cell was converted to an electrochemical hydride generation unit to generate arsine by changing power supply and the direction of the electrical field. Finally, the arsine generated in the working chamber was separated using a gas–liquid separator and detected by atomic fluorescence spectrometry. Potential factors that affect the extraction and hydride generation were investigated in detail. The precision (RSD, n = 10) ranged from 2.3–3.5% for peak area response for As(V) at the 2 μg L−1 level. A detection limit (3σ) of 0.020 μg L−1 As(V) was achieved. The recoveries of three samples ranged from 98 to 104%. The results obtained by the method for As(V) in the certified reference material (BW3210) agreed well with the certified values. The proposed method was successfully applied to pre-concentration and speciation of arsenic species in natural water samples.

We report on a novel method for on-line cloud point extraction (CPE) for preconcentration of cadmium ions. It is based on electromagnetic induction-assisted heating (EMIH) of iron particles in a packed bed contained in a quartz tube that acts as an on-line CPE enrichment column. The cadmium complex of 1-(2-pyridylazo)-2-naphthol is quantitatively retained by the column under the cloud point temperature with the help of EMIH. The column was then eluted with alcoholic borax buffer at room temperature and on-line coupled to FAAS. Under optimum conditions, the limit of detection (3 sb/b) and limit of quantification (10 sb/b) are 0.21 μg L−1 and 0.70 μg L−1 of Cd(II), respectively, and the relative standard deviation is 3.8 % (for n = 8; at 20 ng mL−1). An enhancement factor of 76 is typically achieved. The correlation coefficient of the calibration graph using the present method was 0.9986. The method was successfully applied to determine Cd(II) in water samples

In the present work, a novel solid polymer electrolyte hydride generation (SPE-HG) cell was developed. The home-made SPE-HG cell, mainly composed of three components (Nafion®117 membrane for separating and H+ exchanging, a soft graphite felt cathode and a Ti mesh modified by Ir anode), was employed for detecting As by coupling to atomic fluorescence spectrometry (AFS). The H+ generated by electrolysis of pure water in anode chamber transferred to cathode chamber through SPE, and immediately reacted with As3 + to generate AsH3. The relative mechanisms and operation conditions for hydride generation of As were investigated in detail. The developed cell employed water as an alternative of acid anolyte, with virtues of low-cost, more than 6 months lifetime and environment friendly compared with the conventional cell. Under the optimized conditions, the limit of determination of As3 + for sample blank solution was 0.12 μg L− 1, the RSD was 2.9% for 10 consecutive measurements of 5 μg L− 1 As3 + standard solution. The accuracy of the method was verified by the determination of As in the reference Tea (GBW07605) and the developed method was successfully applied to determine trace amounts of As in tobacco samples with recovery from 97% to 103%.

An electrochemical cold vapor generation system with polyaniline modified graphite electrode as cathode material was developed for Hg (II) determination by coupling with atomic fluorescence spectrometry. This electrochemical cold vapor generation system with polyaniline/graphite electrode exhibited higher sensitivity; excellent stability and lower memory effect compared with graphite electrode electrochemical cold vapor generation system. The relative standard deviation was 2.7% for eleven consecutive measurements of 2 ng mL− 1 Hg (II) standard solution and the mercury limit of detection for the sample blank solution was 1.3 рg mL− 1 (3σ). The accuracy of the method was evaluated through analysis of the reference materials GBW09101 (Human hair) and GBW 08517 (Laminaria Japonica Aresch) and the proposed method was successfully applied to the analysis of human hairs.

Flow injection on-line sorption preconcentration and separation in a knotted reactor (KR) was coupled to cold vapor atomic fluorescence spectrometry for the determination of trace mercury in mineral water. Mercury was preconcentrated by on-line formation of mercury diethyldithiocarbamate complex (Hg-DDTC) and absorption of the resulting neutral complex on the inner walls of a knotted reactor. A 20% (v/v) HNO3 solution heated by Electromagnetic induction heating technique was used as eluent to remove the absorbed Hg-DDTC from the KR, and then the vapor mercury generated by mixing the resulting solution and KBH4 was determined on-line by cold vapor atomic fluorescence spectrometry. The 20% HNO3 was used as both the efficient eluent and the required acidic medium for subsequent mercury vapor generation. Using 20% HNO3 instead of conventional organic solvent as eluent, the proposed method is simple, easy operational and environmental friendly. Under the optimal experimental conditions, the sample throughput was approximately 30 per hour with the enhancement factor of 35. The detection limit of mercury was 2.0 ng l−1. The precision (RSD, n = 11) was 2.2% at the 0.1 μg l−1 Hg2+ level.

An integrated electrochemical hydride generation cell, mainly composed of three components (a gas liquid separator, a graphite tube cathode and a reticulate Pt wire anode), was laboratory constructed and employed for the detection of arsenic by coupling to atomic fluorescence spectrometry. This integrated cell was free of ion-exchange membrane and individual anolyte, with the virtues of low-cost, easy assembly and environmental-friendly. Using flow injection mode, the sample throughput could come to 120 h−1 attributed to the small dimension of the cathode chamber. The operating conditions for the electrochemical hydride generation of arsenic were investigated in detail and the potential interferences from oxygen or various ions were also evaluated. Under the optimized conditions, no obvious oxygen quenching effects were observed. The limit of detection of As (III) for the sample blank solution was 0.2 ng mL−1 (3σ) and the relative standard deviation was 3.1% for nine consecutive measurements of 5 ng mL−1 As (III) standard solution. The calibration curve was linear up to 100 ng mL−1. The accuracy of the method was verified by the determination of arsenic in the reference materials GBW08517 (Laminaria Japonica Aresch) and GBW10023 (Porphyra crispata) and the developed method was successfully applied to determine trace amounts of arsenic in edible seaweeds.

A novel, automated on-line pressurized sample digestion system based on electromagnetic induction heating technique was developed to perform solid sample decomposition in acid medium. The efficiency of acid digestion was increased with 0.36 MPa pressure built up in-line by a 0.5 mm id × 25 m length flow restrictor and up to approximately 135 °C reaction temperature. The system's performance was evaluated for on-line digestion of edible seaweeds and subsequent determination of mercury by cold vapor generation atomic fluorescence spectrometry (CVAFS).

An electrochemical hydride generation system was developed for the detection of Te by coupling an electrochemical hydride generator with atomic fluorescence spectrometry. Since TeH2 is unstable and easily decomposes in solution, a reticular W filament cathode was used in the present system. The TeH2 generated on the cathode surface was effectively driven out by sweeping gas from the cathode chamber. In addition, a low temperature electrochemical cell (10 °C) was applied to reduce the decomposition of TeH2 in solution. The limit of detection (LOD) was 2.2 ng ml− 1 and the relative standard deviation (RSD) was 3.9% for nine consecutive measurements of standard solution. This method was successfully employed for determination of Te in soldering tin material.

A new on-line sample digestion system using electromagnetic induction heating technique was developed for the determination of zinc and manganese in tea leaf by flame atomic absorption spectrometry (FAAS). The homemade electromagnetic heating column (EMHC), whose effective diameter was about 1 mm, was composed of a polytetrafluoroethylene (PTFE) outer tube and seven compactly packed PTFE coil-coated iron wires. The pre-digested sample solution was pumped through EMHC and then transferred directly to FAAS for determination. An analytical throughput of 72 samples h−1 was obtained in the present system. Under optimal condition, the detection limits (3σ) of zinc and manganese were 4.2 μg L−1 and 3.0 μg L−1, along with relative standard deviations (R.S.D.) of 3.2% and 3.6% respectively for zinc and manganese. Certified reference materials GBW 07602, GBW 07605 and GBW 08505 were analyzed to validate the proposed method, good agreement was achieved between the certified values and the obtained results.

A new method for the simultaneous determination of As and Sb by using AFS coupled with a newly designed electrochemical hydride generator has been developed. The hydride generator is a tubular electrolytic cell of 28 mm i.d. and 45 mm length, which consists of a graphite tube cathode and a platinum anode. Gaseous hydrides of As and Sb are generated at the cathode. Through a gas–liquid separator, the hydrides are directly transported to the atomizer by an Ar flow for determination. A detection limit of 0.50 and 0.30 μg l−1 (3σ) for As and Sb in synthetic samples containing10 mg l−1 Cu, Ni and Co was obtained, respectively. The precision (n = 11) for 50 μg l−1 As and Sb was 2.1 and 1.5%, respectively. The method was successfully applied for determination of total As and Sb in Chinese medicine samples.

A simple, rapid and reliable method has been developed for the determination of total mercury in mainstream cigarette smoke samples. The method used an electromagnetic induction oven as the heating source to digest sample on-line for the first time, and determined mercury by atomic fluorescence spectrometry equipped with an intermittent flow reactor. The proposed method was successfully applied to the determination of mercury in mainstream cigarette smoke samples.

A novel, automated on-line pressurized sample digestion system based on electromagnetic induction heating technique was developed to perform solid sample decomposition in acid medium. The efficiency of acid digestion was increased with 0.36 MPa pressure built up in-line by a 0.5 mm id × 25 m length flow restrictor and up to approximately 135 °C reaction temperature. The system's performance was evaluated for on-line digestion of edible seaweeds and subsequent determination of mercury by cold vapor generation atomic fluorescence spectrometry (CVAFS).

In this paper we discuss an on-line electrokinetic extraction and electrochemical hydride generation system for inorganic arsenic speciation developed using an H-type integrated cell. The integrated cell, mainly consisting of a working chamber and an auxiliary chamber, was used as both an electrokinetic extraction and an electrochemical hydride generation unit. The As(V) ions in the sample solution was firstly extracted into the working chamber of the H-type integration cell and reduced into As(III). Subsequently, the integrated cell was converted to an electrochemical hydride generation unit to generate arsine by changing power supply and the direction of the electrical field. Finally, the arsine generated in the working chamber was separated using a gas–liquid separator and detected by atomic fluorescence spectrometry. Potential factors that affect the extraction and hydride generation were investigated in detail. The precision (RSD, n = 10) ranged from 2.3–3.5% for peak area response for As(V) at the 2 μg L−1 level. A detection limit (3σ) of 0.020 μg L−1 As(V) was achieved. The recoveries of three samples ranged from 98 to 104%. The results obtained by the method for As(V) in the certified reference material (BW3210) agreed well with the certified values. The proposed method was successfully applied to pre-concentration and speciation of arsenic species in natural water samples.